This Month’s Annular Solar Eclipse…
There are many fascinating and beautiful events to witness in the Universe but by far the most spectacular is the solar eclipse. For centuries mankind has been fascinated, even scared of them and would offer sacrifices to the Gods to get it back. In reality, these stunning events take place when the Moon passes directly between the Earth and the Sun, blocking the latter from our view. But on 10th May another type of solar eclipse will be on show for those lucky enough to be in the right place to see it!
As luck would have it, the apparent size of the Moon and Sun are almost identifcal in the sky. This is just co-incidence and if we had been alive many thousands of years ago, the Moon would have appeared a little bigger. The tidal interraction of the Moon and Earth are causing the Moon to slowly move away from us causing this slow decrease in the size of the Moon. In addition to all of this, the orbit of the Moon around the Earth is very slightly elliptical which means sometimes it is closer and other times, more distant.
At these more distant points known as apogee, the Moon is slightly smaller in the sky than the Sun and it is this that will occur on 10th May. Down on Earth we will see this as the Moon passing in front of the Sun but it will not be large enough to complete obscure the Sun so a ring of sunlight will still be visible. These events are called annular eclipses and this one will be visible along a path which crosses the Pacific Ocean. It will be seen from Australia, Papua New Guinea, the Solomon Islands and the Gilbert Islands. From most other parts of the Pacific Ocean, it will be visible as a partial eclipse. The annular phase of the eclipse first hits the surface of the Earth at 22:33 UTC on 10th May and finishes at 02:20 UTC on the 11th May.
Caution is needed to observe annular or partial eclipses as at no point is it safe to look directly at it without some form of protection; unlike total solar eclipses where the moment of totality is safe to look at. The best way to watch the eclipse is to either project the image through a telescope or binoculars or better still, to use special eclipse viewing glasses available from many astronomy suppliers.